The Associated Press called it after 522 of 681 precincts or 77% reported. At that point Gianforte had 163, 539 votes, or 51% of the vote, compared with challenger Rob Quists 140,594 votes, or 44%.

Speaking at the G7 meeting in Sicily on Friday, Donald Trump called the victory a great win in Montana.

After emerging from a blue curtain to greet a cheering crowd on Thursday night, Gianforte apologized for his actions on Wednesday, talking past the laughter of the crowd to say: Last night, I made a mistake and I took an action that I cant take back, and Im not proud of what happened. I should not have responded the way that I did and for that Im sorry.

A member of the crowd shouted: And youre forgiven.

Gianforte continued: I should not have treated that reporter that way, and for that Im sorry, Mr Ben Jacobs.

The congressman-elect went on to run through his campaign themes, promising to work with the Trump administration and drain the swamp. It just seems when people go to Washington DC they just drink the water and slither into the swamp, he said, before announcing that he would continue to live in Montana and commute to the capitol. Montana sent a strong message tonight that we want a congressman who will work with President Trump to make Montana and America great again, he said.

He touched on public lands, veterans, the second amendment, and balancing the budget in his speech, but made no mention of the Republican healthcare bill the topic of the question that he refused to answer on Wednesday.

Quist told supporters he called Gianforte and stressed the need to listen to all Montanans, adding he was sure that Montanans will hold Mr Gianforte accountable.

On Wednesday afternoon, Gianforte was at his Bozeman campaign headquarters for a volunteer barbecue when he was approached by Guardian reporter Ben Jacobs. When Jacobs asked Gianforte a question about the Republican healthcare bill, Gianforte threw Jacobs to the ground and punched him.

Gianfortes campaign spokesman released a statement blaming the altercation on Jacobs, but audio of the incident captured by Jacobs and the eyewitness statements from three Fox News reporter who were in the room at the same time, as well as a Buzzfeed reporter just outside the room, backed up Jacobs account. Late Wednesday evening, the Gallatin county sheriffs office charged Gianforte with misdemeanor assault.

The electoral impact of Gianfortes outburst the audio of which was quickly turned into a radio advertisement for Quist was blunted by the large proportion of early voters in the state. More than 250,000 vote-by-mail ballots had been cast by Wednesday evening.

Gianforte supporter Diane Willard, a retired stockbroker and member of Gianfortes church, praised him for his philanthropy and said the Republican businessman was nothing but honorable and gracious. Like many of Gianfortes supporters, she blamed Jacobs for the altercation.

Whatever that guy did had to be awful, she claimed. Ive never seen [Gianforte] even angry.

Bruce McGee, a Republican alderman from Laurel, Montana, traveled two hours by bus to attend the party. McGee said he was a little disappointed about the assault, but that Gianforte still had his undying support.

The scandal might even have an upside, he said. It certainly propelled him into the national spotlight, he said. So many of these things are providence.

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Reporter shares account of alleged ‘body-slam’ by GOP candidate video

Ileana Indreland, who works in real estate in Bozeman, said the altercation was a symptom of Americans getting tired of the bullying media. I used to dance to Rob Quists band, and they were a fun band, she said. But she credited Gianforte with a superior depth of knowledge about policy, and said his background in technology and business would be good for the state.

The special election was called to replace Republican Ryan Zinke, who was confirmed as secretary of the interior on 1 March. The unexpectedly competitive race pitted Gianforte, a transplant who made a fortune running a local software company, against Democrat Quist, a Montana native and a popular folksinger.

The race soon became a focus for national attention as a testing ground for the popularity of both Trump and the Republican proposals to repeal and replace Obamacare. Over $17m was eventually spent on behalf of both candidates in the rural states truncated special election. Both candidates had deep flaws. Gianforte, whom one top Republican operative derided as a C- minus candidate, was unpopular with voters and was stiff and wooden on the stump. Quist, a first time candidate, had little policy knowledge and came under scrutiny over his checkered financial history.

Although Montana has notoriously quirky politics and a fondness for ticket-splitting, the national political environment has had a major influence in a state that Donald Trump won by over 20 points.

For the special election, Gianforte embraced Trumps rhetoric on draining the swamp, touring with Donald Trump Jr, and promising voters to work closely with the administration if elected. He also adopted Trumps hostile attitude toward the press, drawing rebukes from local editorial boards even before he allegedly attacked a reporter.

This served as a contrast from his 2016 campaign for governor against incumbent Democrat Steve Bullock. Gianforte distanced himself from Trump and lost by four points in a state where the Republican presidential nominee romped to victory.

Quist ran as an unapologetic progressive and barnstormed the state with Vermont Senator Bernie Sanders the weekend before the election. A political neophyte, Quist relied on his local celebrity from his music career as well as denouncing his Republican opponents for wanting to privatize public lands and dismantle Obamacare.

Though Gianfortes altercation dominated the airwaves on election day, it made little difference to several Bozeman residents casting their vote at the Gallatin county fairgrounds on Thursday evening. For Quist voters, the allegation confirmed their choice, while Gianforte voters expressed skepticism that the Republican had done anything wrong.

It got really blown out of proportion, said David Runia of the assault. I think the reporter is the one who should be charged, if anything.

We know him, added Hannah Runia, speaking of Gianforte. Hes a great guy.

Lowell Springer, another Gianforte voter, agreed. Hes a very polite guy, he said. Theres an end to everyones patience.

Colter Dykman, a finance manager and Quist supporter, said that the incident had given him hope that his candidate might win.

If that doesnt change your vote, where do you draw the line? he asked.

But overall, no one seemed particularly shocked that the campaign season had come to this.

Seth Thomas, who declined to state how he voted, said that the incident had tarnished Gianfortes reputation, but added: Everyone gets in fights in Montana.